Extruder die with additive reservoir

ABSTRACT

An extruder die assembly and method for using same is disclosed which is designed for adaptation to a wide variety of commercial-grade extrusion devices common in the food industry. The extruder die assembly is inserted into an appropriate compartment within an extrusion device such that a first extrudate is directed down a coaxially aligned passageway within the forming section and combined with a fluid additive in the injection section whereupon the resulting food mass is compressed through a converging nozzle bore in the nozzle section to produce an extruded food product. The forming section and injection section are fabricated as a matching set. The matched set, comprising the forming section and the injection section, when properly aligned and coupled form an internal peripheral reservoir manifold through which a fluid additive may be supplied to at least one and more preferably a plurality of capillary channels which in turn impart a distinct cross-sectional design into a flowing mass of a first extrudate.

BACKGROUND OF THE INVENTION

[0001] 1. Technical Field

[0002] The present invention generally relates to an apparatus andmethod for adding a fluid additive into an extrudable food mass, andmore particularly, to an improved extruder die assembly and method forusing same to impart a distinct colored and/or flavored pattern into anextrudable food mass during extrusion.

[0003] 2. Description of the Related Art

[0004] The use of extrusion devices is prevalent in a number ofindustries, especially the food industry. Utilized to produce a varietyof products such as ready-to-eat (R-T-E) cereals, snack foods andconfections, extrusion remains prominent among food processes because ofits versatility and efficiency.

[0005] Food processes utilizing extrusion devices typically include anedible substance such as dough which is introduced into a device andconveyed via a screw pump to an inlet where the substance is forcedthrough an extruder die. The extruder die may perform a variety offunctions: it may form or shape the extrudate; it may divide theextrudate into a multiple extrudates; it may inject an additivesubstance into the extrudate; and it may compress and reduce thecross-sectional area of the extrudate. Examples of devices used forextrusion of food products are illustrated in U.S. Pat. Nos. 2,858,217;3,314,381; and 5,639,485. While extrusion dies have evolved over theyears, the method by which an additive substance is supplied andinjected into the extrudate has remained essentially unchanged.

[0006] For Example, in U.S. Pat. No. 2,858,217 to Benson, theintroduction of coloring matter, such as a colored liquid dye, isaccomplished via a series of apertures 40, 42, 44 disposed in thebridging strips 32, 34, 36 and supplied by horizontal passages 52, 54,55 which are in fluid communication with the dye reservoir 46. Thesupplying of the liquid dye from the dye reservoir 46 to series ofapertures 40, 42, 46 is by means of gravitational force. According tothe Benson '217 device, dough material 18 is extruded through a dividerblock 22 which forces the dough material 18 to divide or spread aroundthe bridging strips 32, 34, 36 so that voids 38 are formed into whichthe coloring matter is introduced via the series of apertures 40, 42,44.

[0007] Similarly, in U.S. Pat. No. 3,314,381 to Fries et al., the fluidinjection assembly is comprised of a hollow tubular injection member 29in a helical spiral configuration, which includes a bore 37 throughwhich pressurized injection fluid is supplied from a source 25 to aplurality of longitudinally spaced bores 39 into a distributing channel38. The fluid along the length of channel 38 is injected into thepassing dough as a substantially longitudinally continuous spiral bandextending from substantially the central axis of the dough to either theouter face of the dough or a point short thereof. However, the Fries etal. '381 device is primarily adapted to relatively low pressurecomestible extrusions.

[0008] Finally, U.S. Pat. No. 5,639,485 to Weinstein et al. and itsrelated patents, disclose a method and apparatus for adding additives inflowing dough to make complexly patterned multicolored extrudates. TheWeinstein et al. '485 invention and its progeny all disclose a highpressure extrusion device comprising an extruder die insert 20 whichincludes means for imparting at least one interstitial gap in theflowing dough by means of a plurality of dividing passageways (e.g., 44,45, 46) formed by die dividing members 47. An additive (e.g., a foodcolor or a second colored dough) may be injected via a plurality orarray of evenly spaced food color injection ports 48 formed on thedownstream side of die dividing member 47. The injection ports 48 are influid communication with a pressurized color supply 18 by means of asupply ports 52, 54, 56 and supply passageway 50. The color fluid tendsto fill the interstitial gaps in the flowing dough between passageways(e.g., 44, 45, 46) formed by and behind the die dividing members 47 tocreate a line in the shape of dividing members 47 in the extruded dough.The die insert 20 also includes notches 57 which are used to isolate thecolor fluid injected into the interstitial gap from spreading to theinterior surface wall of die insert 20 thereby reducing if noteliminating the leakage on color fluid onto the outside of the extrudeddough. Additionally, the die insert 20 can further include a means forsealing (e.g., “O” rings 60 and 62 as depicted) the color fluid supplyreservoir 58 against premature admixture with dough.

[0009] In addition to the die insert element, the Weinstein et al. '485invention also comprises a reducing passageway 25 whereby theextrudate's cross-sectional area is significantly reduced. At highoperating pressures, the convergence of the passageway 25 inherentlycreates a significant back pressure on the downstream side of theextruder die insert 20 which, in turn, can contribute to and promote theclogging of the individual injection ports 48. Moreover, the utilizationof notches 57, sealing means 60, 62 and multiple enclosed injectionports 48 further complicates the design of the die insert making itharder to clean and maintain. Finally, injecting color fluid at discretelocations into downstream voids or interstitial gaps to disperse thefluid in a generally uniform manner requires precise control of flowrates, internal pressures, and viscosity of the extrudate and variousadditives. Furthermore, the design of each die insert 20 is limited tothe physical constraints imposed by the previously mentioned designelements.

[0010] What is needed is an extruder die capable of operating at avariety of operating pressures which has improved seal characteristicsand is simpler and easier to maintain and whose injection mechanism isless prone to clogging and blockages.

SUMMARY OF THE INVENTION

[0011] The present invention overcomes many of the shortcomings inherentin previous methods and systems addressing extruder die assemblies. Thepresent invention comprises an improved extruder die assembly and methodfor using same to impart a distinct colored and/or flavored pattern intoan extrudable food mass during the extrusion process.

[0012] In one embodiment, the system comprises an extruder die assemblyand method for using same which includes a forming section and aninjection section fabricated as a matching set. When properly alignedand coupled, the matching set forms a peripheral reservoir manifold,internal to the die assembly, through which a fluid additive may besupplied via a supply port to at least one and more preferably aplurality of capillary channels which in turn impart a distinctcross-sectional design into a flowing mass of a first extrudate.

[0013] In another embodiment, the system and method for using thepresent invention includes partitioning the internal peripheralreservoir manifold so that a plurality of supply ports may be used toallow different colors and/or flavors to be injected at differentlocations in the distinct cross-sectional design.

[0014] In another embodiment, the system and method for using sameutilizes multiple matched sets of forming sections and injectionsections in tandem to impart multiple pattern designs into an extrudablefood mass.

[0015] In another embodiment, the system and method for using sameutilizes multiple matched sets of forming sections and injectionsections in tandem to impart multiple pattern designs of differingcolors and/or flavors into an extrudable food mass.

[0016] In another embodiment, the system and method for using sameutilizes a converging nozzle to decrease the extrudate's cross-sectionalarea while maintaining the distinct cross-sectional design patternimparted into the extrudate.

[0017] Thus, in accordance with one feature of the invention, thepresent invention is comprised of an extruder die assembly capable ofoperating at a variety of operating pressures which has improved sealcharacteristics and is simpler and easier to maintain. Moreover, theperformance of the extruder die assembly of the present invention ismore stable in that surging of the fluid additive is inhibited therebyresulting in a continuous well defined pattern being injected into theextrudable food mass.

[0018] In accordance with another feature of the invention, the presentinvention is comprised of an extruder die assembly whose injectionmechanism is less prone to clogging and blockages. The system of thepresent invention allows the flow of the extrudable food mass to bemomentarily halted without permanently plugging the supply passagewaysor injection section(s).

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The novel features believed characteristic of the invention areset forth in the appended claims. The invention itself, however, as wellas a preferred mode of use, further objectives and advantages thereof,will best be understood by reference to the following detaileddescription of an illustrative embodiment when read in conjunction withthe accompanying drawings, wherein:

[0020]FIG. 1a is a cut-away perspective view of the extruder dieassembly of the present invention;

[0021]FIG. 1b is a cut-away exploded perspective view of the extruderdie assembly of the present invention;

[0022]FIG. 2a is an overhead view of the forming section of the extruderdie assembly of the present invention;

[0023]FIG. 2b is a cut-away perspective view of the forming section ofthe extruder die assembly of the present invention;

[0024]FIG. 3a is an overhead view of the injection section of theextruder die assembly of the present invention; and

[0025]FIG. 3b is a cut-away perspective view of the injection section ofthe extruder die assembly of the present invention.

[0026] Where used in the various figures of the drawing, the samenumerals designate the same or similar parts. Furthermore, when theterms “top,” “bottom,” “first,” “second,” “upper,” “lower,” “height,”“width,” “length,” “end,” “side,” “horizontal,” “vertical,” and similarterms are used herein, it should be understood that these terms havereference only to the structure shown in the drawing and are utilizedonly to facilitate describing the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0027] An extruder die assembly, generally indicated by referencecharacter 100 in FIGS. 1a and 1 b, includes a forming section 200, aninjection section 300, and a nozzle section 400. The three sectionscomprising the die assembly 100 are coaxially aligned and interlocking.Additionally, means for coupling the forming section 200 to theinjection section 300 are also included.

[0028] The extruder die assembly 100 is designed for adaptation to awide variety of commercial-grade extrusion devices common in the foodindustry. The extruder die assembly 100 is inserted into an appropriatecompartment within an extrusion device (not shown) such that a firstextrudate (e.g., a paste or a cereal dough) is directed down a coaxiallyaligned passageway 210 within the forming section 200 and combined witha fluid additive (e.g., a food coloring dye or a flowable colored and/orflavored food material) in the injection section 300 via supply port 340and annular reservoir R, whereupon the resulting food mass is compressedthrough a converging nozzle bore 420 in the nozzle section 400 toproduce an extruded food product containing a distinct colored and/orflavored pattern.

[0029] While the embodiment illustrated is shown as being generallycylindrical in shape, the exterior housing of the die assembly 100 maybe of any shape necessary for adaptation to commercial-grade extrusiondevices common in the food industry. Similarly, while passageway 210 andbore 420 are depicted as having a circular cross sectional area, inother embodiments, passageway 210 and bore 420 can be fabricated with amore complex peripheral configuration to define or define in part theexterior shape or configuration of the finished piece, including bothregular shapes (e.g., stars, rings, geometric shapes) as well asirregular shapes (e.g., animals, vegetables, objects such as trees,cars, etc.).

[0030] Referring to the figures, and in particular FIGS. 2a and 2 b, theforming section 200 is a generally tubular flange element having acentral bore defining a passageway 210. The inlet 212 of the passageway210 is adapted to receive a conduit (not shown) supplying a pressurizedfirst extrudate from an extrusion device (not shown). A plurality ofcounter-sunk coupling holes 202, equally spaced around the periphery ofthe entrance face 204 of forming section 200, are provided for receivingscrews (not shown) for removably coupling the forming section 200 tothreaded holes 302 in the injection section 300. An alignment hole 206extends through the forming section 200 in parallel alignment with thepassageway 210 to receive an alignment knob 306 on the entrance face 304of the injection section 300. When properly seated into the alignmenthole 206, the alignment knob 306 ensures that the axial angularalignment of the injection section 300 in relation to the formingsection 200 is correct.

[0031] The outlet portion of the passageway 210 includes a forming dieelement 220 which divides the flow of the first extrudate into at leasttwo, and more preferably a plurality of adjacent flowing extrudatepassageways such as passageways a-g respectively formed by forming dieelement 220.

[0032] The forming section and injection section are fabricated as amatching set. In general, the outlet portion of the forming section isdesigned to mate and seal with the inlet portion of the injectionsection. In one embodiment, an inner peripheral rim formed in the outletportion of the forming section is specifically designed to slidablycouple and align with a central bore in the inlet portion of theinjection section. The inner peripheral rim is defined by a peripheralnotch formed in the outlet face of the forming section. The peripheralnotch is characterized by a peripheral rim wall which is parallel withand generally equidistant from the outer periphery of the centralpassageway. The inner peripheral rim includes a peripheral groove with asemicircular cross-section. A matching peripheral groove with asemicircular cross-section is formed in the base of the central bore ofthe inlet portion of the injection section such that when the formingsection and injection section are slidably coupled and aligned, aninternal peripheral reservoir manifold with a circular cross-section isformed.

[0033] Thus, as shown in the figures, and in particular FIGS. 2b, 3 a,and 3 b, when the present invention is realized in an embodiment havinga generally circular cross section, the inner peripheral rim formed inthe outlet portion of the forming section 200 is an annular rim definedby an annular notch, characterized by the annular rim wall 242 and theannular outer ring seal face 240, around the outer periphery of theoutlet face of the forming section 200. The annular rim in the outletportion of the forming section 200 slidably fits into a central bore inthe inlet portion of the injection section 300 defined by the annularbore wall 308 such that the forming section's annular outer ring sealface 240 seats and seals with the injection section's annular outer sealface 304, the forming section's intermediate annular seal face 244 seatsand seals with the injection section's annular intermediate ring sealface 310, and the forming section's inner annular seal face 246 and theexit face 248 of the forming die element 220 seat and seal with theentrance face 322 of the injection section's co-injection die insert320. Moreover, the matching annular peripheral grooves 230 and 330 forman annular internal peripheral reservoir manifold R into which a fluidadditive may be supplied. When properly aligned and coupled, therespective annular seals between the forming section 200 and thematching injection section 300 effectively seal and isolate the fluidadditive supplied to the reservoir manifold R from inadvertent leakageto the upstream side of the forming die element 220 and the outerperiphery of the extruder die assembly 100.

[0034] The injection section 300 includes a co-injection die insert 320which has profile such that when properly aligned with the forming dieelement 220, passageways a′-g′ are respectively adjoined withpassageways a-g formed by forming die element 220. When properly alignedand coupled, the seal between the exit face 248 of the forming dieelement 220 and the entrance face 322 of the injection section'sco-injection die insert 320 ensures that the respective adjacentlyflowing extrudate passageways are unobstructed and contiguous and thatthe fluid additive contained in the reservoir manifold R does notinadvertently leak to the upstream side of the forming die element 220.

[0035] The co-injection die insert 320 includes at least one and morepreferably a plurality of capillary channels 352 in the space betweenthe plurality of passageways. The capillary channels 352 are fluidlyconnected to the reservoir manifold R via channel ports 350. Thereservoir manifold R is fluidly connected to a pressurized source offluid additive (not shown) via supply port 340.

[0036] When properly aligned and coupled, the seal between the exit face248 of the forming die element 220 and the entrance face 322 of theinjection section's co-injection die insert 320 ensures that thepressurized fluid additive supplied to the annular internal peripheralreservoir manifold R continually charges the capillary channels 352 viachannel ports 350 whereupon each capillary channel 352 emits at itsdownstream exit face a continuous discharge of fluid additive in thegeneral cross-sectional shape of the capillary channel 352 resulting ina continuous band of fluid additive being injected into the transientclefts formed in the first extrudate as it exits the adjacent flowingextrudate passageways such as passageways a′-g′. Upon exiting from theindividual adjacent flowing extrudate passageways (e.g., passagewaysa′-g′), the individual adjacently flowing columns of first extrudatecoalesce to enclose the injected bands of fluid additive within a singleflow mass thereby imparting a distinct colored and/or flavored patterninto the food mass.

[0037] In an alternative embodiment of the present invention, theinjection section 300 may include multiple supply ports 340 fluidlyconnected to separate pressurized sources of fluid additive. In such anembodiment, the annular internal peripheral reservoir manifold R may bedivided into multiple segregated quadrants fluidly connecting individualpressurized sources of fluid additive to specific capillary channels 352allowing a distinct pattern of multiple colors and/or flavors to beimparted into the food mass.

[0038] In one embodiment of the present invention, the exit face of theinjection section 300 is generally designed to mate and seal with theinlet face of the nozzle section 400. With the exception of theco-injection die insert 320, the inlet face of the nozzle section 400 isessentially a mirror image of the exit face of the injection section300. In general, the nozzle section 400 includes an inlet with aperiphery matching the periphery of the forming section's passageway.The nozzle section further includes a passageway coaxially aligned withthe forming section's passageway which converges to an outlet. As thepassageway converges, the passageway's cross-sectional decreases whileits aspect ratio is generally maintained. Thus as shown in the figures,and in particular FIGS. 1b and 3 b, when the present invention isrealized in an embodiment having a generally circular cross section, thenozzle section 400 includes an inlet 410 with an inner annular peripherywhich matches the periphery of the forming section's passageway 210. Thenozzle section further includes a passageway 420 coaxially aligned withthe forming section's passageway 210 which converges to an outlet 430.

[0039] In an actual embodiment having a circular cross section asillustrated in FIG. 1b, the diameter of passageway 420 is reduced from0.664 inches at inlet 410 to 0.332 inches at outlet 430. In another suchembodiment, the diameter of passageway 420 is further reduced from 0.664inches at inlet 410 to 0.153 inches at outlet 430.

[0040] Alternatively, in another embodiment of the present invention,multiple sets of matching forming/injection sections may be adjoined ina tandem or series arrangement. In such an embodiment, the inlet face ofa second set's forming section is designed to mate and seal with theexit face of a first set's injection section. Arranging multiple sets ofmatching forming/injection sections in tandem allows multiple patterndesigns of differing colors and/or flavors to be imparted into anextrudable food mass.

[0041] It will now be evident to those skilled in the art that there hasbeen described herein an improved extruder die apparatus and method forimparting a distinct colored and/or flavored pattern into an extrudablefood mass during extrusion. Although the invention hereof has beendescribed by way of a preferred embodiment, it will be evident thatother adaptations and modifications can be employed without departingfrom the spirit and scope thereof. For example, multiple extrusion dieassemblies may be utilized in a parallel arrangement by a singleextruder device. The terms and expressions employed herein have beenused as terms of description and not of limitation; and thus, there isno intent of excluding equivalents, but on the contrary it is intendedto cover any and all equivalents that may be employed without departingfrom the spirit and scope of the invention.

What is claimed is:
 1. An extruder die assembly for imparting a distinctpattern into an extrudable food mass during extrusion, comprising: (a) aforming section comprising, (i) an entrance face having an inlet, (ii) acentral passageway extending from the inlet to an outlet, (iii) aforming die element traversing the central passageway, and (iv) an exitface having a first peripheral groove which circumscribes the outlet;(b) an injection section comprising, (i) an entrance face having asecond peripheral groove circumscribing a co-injection die insert; (1)said co-injection die insert having at least one capillary channel influid communication with the second peripheral groove, (a) wherein saidcapillary channel includes an upstream discharge and a downstreamdischarge, (ii) a supply port fluidly connecting the second peripheralgroove to a fluid additive source; and (c) means for coupling andsealing the exit face of the forming section to the entrance face of theinjection section thereby positioning and aligning: (i) the first andsecond peripheral grooves so as to form and isolate a peripheralreservoir manifold therebetween, (ii) the forming die element and theco-injection die insert so as to seal the upstream discharge of thecapillary channel.
 2. The extruder die assembly of claim 1 furthercomprising in interlocking, coaxially aligned combination: (d) a nozzlesection comprising (i) an entrance face having an inlet, (ii) aconverging passageway, and (iii) an outlet.
 3. The extruder die assemblyof claim 1, wherein the first and second peripheral grooves furtherinclude a plurality of partitioning walls which when properly aligneddivide the peripheral reservoir manifold into a plurality of peripheralreservoir manifold spaces, and wherein element (b)(ii) comprises aplurality of separate supply ports each fluidly connecting one of theplurality of reservoir manifold spaces in the second peripheral grooveto one of a plurality of fluid additive sources.
 4. The extruder dieassembly of claim 2, wherein the cross sectional area of the convergingpassageway is reduced by a factor not greater than 20:1 between theinlet and the outlet of the nozzle section.
 5. The extruder die assemblyof claim 4, wherein the cross sectional area of the convergingpassageway is reduced by a factor greater than 4:1 between the inlet andthe outlet of the nozzle section.
 6. An extruder die assembly forimparting a distinct pattern into an extrudable food mass duringextrusion, comprising, in interlocking, coaxially aligned combination:(a) a plurality of matched sets in tandem alignment, each set comprising(i) a forming section comprising, (1) an entrance face having an inlet,(2) a central passageway extending from the inlet to an outlet, (3) aforming die element traversing the central passageway, and (4) an exitface having a first peripheral groove which circumscribes the outlet;(ii) an injection section comprising, (1) an entrance face having asecond peripheral groove circumscribing a co-injection die insert; (a)said co-injection die insert having at least one capillary channel influid communication with the second peripheral groove, (i) wherein saidcapillary channel includes an upstream discharge and a downstreamdischarge, (2) a supply port fluidly connecting the second peripheralgroove to a first fluid additive source; and (iii) means for couplingand sealing the exit face of the forming section to the entrance face ofthe injection section thereby positioning and aligning: (1) the firstand second peripheral grooves so as to form and isolate a peripheralreservoir manifold therebetween, (2) the forming die element and theco-injection die insert so as to seal the upstream discharge of thecapillary channel.
 7. The extruder die assembly of claim 6 furthercomprising in interlocking, coaxially aligned combination: (b) a nozzlesection comprising (i) an entrance face having an inlet, (ii) aconverging passageway, and (iii) an outlet
 8. The extruder die assemblyof claim 7, wherein the cross sectional area of the convergingpassageway is reduced by a factor not greater than 20:1 between theinlet and outlet of the nozzle section.
 9. The extruder die assembly ofclaim 8, wherein the cross sectional area of the converging passagewayis reduced by a factor greater than 4:1 between the inlet and outlet ofthe nozzle section.
 10. An extruder die assembly for imparting adistinct pattern into an extrudable food mass during extrusion,comprising, in combination: (a) means for supplying a first extrudateflow wherein said means for supplying comprises means for receiving anddirecting the first extrudate flow down a central passageway; (b) meansfor imparting at least one cleft in the first extrudate flow therebydividing the first extrudate flow into a plurality of adjacent flowingextrudate flows, (c) means for injecting a fluid additive into the atleast one cleft between the plurality of adjacent flowing extrudateflows, (i) wherein the injecting means comprises a co-injection dieinsert having at least one capillary channel in fluid communication witha peripheral reservoir manifold circumscribing the injection assembly,(ii) wherein the injection means further comprises a supply port fluidlyconnecting the peripheral reservoir manifold to a fluid additive source;and (d) means for coalescing the plurality of adjacent flowing extrudateflows into a second extrudate flow while generally maintaining the fluidadditive's relative position between the plurality of adjacent flowingextrudate flows; and (e) means for reducing the cross sectional area ofthe second extrudate flow.
 11. The extruder die assembly of claim 10,wherein means for reducing further comprises means for reducing thecross sectional area of the second extrudate flow by a factor notgreater than 20:1.
 12. The extruder die assembly of claim 11, whereinmeans for reducing further comprises means for reducing the crosssectional area of the second extrudate flow by a factor of more than4:1.
 13. The method of claim 10, wherein the fluid additive is colored.14. The method of claim 13, wherein the fluid additive is colored a hueor shade different than the first extrudate.
 15. The method of claim 10,wherein the fluid additive is flavored.
 16. The method of claim 15,wherein the fluid additive is flavored a different flavor than the firstextrudate.
 17. A method for imparting a distinct pattern into anextrudable food mass during extrusion, said method comprising, incombination, the following steps: (a) supplying a first extrudate flowwherein said supplying step comprises receiving and directing the firstextrudate flow down a central passageway, (b) imparting at least onecleft in the first extrudate flow thereby dividing the first extrudateflow into a plurality of adjacent flowing extrudate flows (c) injectinga fluid additive into the at least one cleft between the plurality ofadjacent flowing extrudate flows (i) wherein the injecting step utilizesa co-injection die insert having at least one capillary channel in fluidcommunication with a peripheral reservoir manifold circumscribing theinjection assembly, (ii) wherein the injection step further utilizes asupply port fluidly connecting the peripheral reservoir manifold to afluid additive source; and (f) coalescing the plurality of adjacentflowing extrudate flows into a second extrudate flow while generallymaintaining the fluid additive's relative position between the pluralityof adjacent flowing extrudate flows.
 18. The method of claim 17 furthercomprising (g) reducing the cross sectional area of the second extrudateflow by a factor not greater than 20:1.
 19. The method of claim 18further comprising reducing the cross sectional area of the secondextrudate flow by a factor greater than 4:1.
 20. The method of claim 17,wherein the fluid additive is colored.
 21. The method of claim 20,wherein the fluid additive is colored a hue or shade different than thefirst extrudate.
 22. The method of claim 17, wherein the fluid additiveis flavored.
 23. The method of claim 22, wherein the fluid additive isflavored a different flavor than the first extrudate.